1. Technical Field
Example embodiments of the present invention relate in general to machine type communication (MTC), and more specifically, to an apparatus and a method for transmitting uplink data of machine type communication user equipment (MTC UE) that uses a bandwidth of 1.4 MHz (or 3 MHz or 5 MHz) in an MTC system based on 3rd generation partnership project long term evolution (3GPP LTE).
2. Related Art
Machine type communication (MTC) or machine to machine communication denotes a type of data communication associated with at least one entity that does not necessarily require human intervention.
Services that are optimized for MTC are characterized differently from current mobile network communication in that the services are associated with characteristics such as a) a variety of market scenarios, b) data communication, c) lower costs and effort, d) a significantly large number of potential terminals that communicate, and e) a significantly small amount of traffic for each terminal up to a large range.
MTC may be exhibited in the form of various services, and as examples of the various services, smart metering, tracking and tracing, remote maintenance and control, e-Health, and the like may be given.
In current 3rd generation partnership project (3GPP), standardization of MTC is in progress using the term “MTC”. Until now, the standardization of MTC has been discussed only in upper layers mainly related to networks and systems, but discussion related to MTC really began even in physical levels starting from the 3GPP standardization meeting in October 2011.
According to long term evolution (LTE) standard, signal bandwidths of 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz are supported for communication between an LTE terminal and a base station. The base station uses only one of these bandwidths (for example, 20 MHz), and the LTE terminal should support all bandwidths since the bandwidth that the base station will use for each cell cannot be known.
However, machine type communication user equipment (MTC UE) is expected to be used for transmitting a significantly small amount of information according to applications, and therefore supporting all the bandwidths is exceedingly inefficient in respect of unit cost of the terminal and power consumption. In the current 3GPP standardization meeting, contributions related to MTC UE with a narrow bandwidth of 1.4 MHz have been suggested. That is, even though a bandwidth of the base station is wider than 1.4 MHz, the MTC UE supports only the bandwidth of 1.4 MHz. In addition, in order to transmit data such as moving pictures, even a suggestion such that MTC UE should support a bandwidth of 3 MHz or 5 MHz has been made.
As a representative example of use of MTC applications, smart metering that informs gas usage may be given, and in the smart metering, data transmission rate of MTC is significantly small. Even in the standardization meeting, requirements of MTC UE which should support at least the transmission rate with a lower limit of 118.4 Kbps and with an upper limit of 59.2 Kbps have been determined.
Therefore, since a large number of MTC UE may exist in a single cell, there is a waste problem in terms of frequency resource utilization when a single MTC UE uses overall a single resource block (RB) assigned to the MTC UE having a small transmission rate as described above.
Hereinafter, an LTE terminal denotes a terminal having 3GPP LTE standard that supports all bandwidths of 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz, and an MTC UE denotes a terminal that supports bandwidths of 1.4 MHz, 3 MHz, or 5 MHz based on LTE.